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Short-term gremlins. While OSX 10.6.7 instantly recognized the standard USB input, the hiFace eluded recognition even though I'd pre-installed the necessary M2Tech driver for the OEM hiFace modules in the Human Audio Libretto HD and my Esoteric UX1/APL Hifi NWO-M both of which showed up instantly as selectable output devices each time a USB cable connected them to my iMac. Help.
"It is very difficult to make recommendations with off-site software and complicated OS like Windows or OSX because the set-up of drivers and applications is important as is the hardware version. When issues with OS software arise it always requires investigating the actual computer.


"Here it is reasonable only to recommend the common sequence. Install the necessary driver from this link. Currently the hiFace is compatible with Windows 7, Vista and XP; and OS 10.6 (Snow Leopard), 10.5 (Leopard, both PPC and Intel) and 10.4 (Tiger). Connect a USB cable from the computer to the USB1 input  of the preamplifier. Launch an appropriate player. Select the output device 'M2Tech hiFace' from this player." This of course didn't tell me anything I didn't already know or had done. The Fonel simply wasn't selectable. Thankfully two OSX updates later the Fonel finally returned from its unauthorized leave to shake hands properly. M2Tech's Marco Manunta's guess that something related to the power-up of the board was too slow to interrupt negotiation with the USB bus proved not so.

Core sonics: Fonel's shunt-regulated push/pull tube circuit or SRPP "is an elegantly simple circuit and really a small output transformer-less amplifier. It was widely used in TV circuits for delivering significant current into heavy capacitive loads. It was first patented in 1940 by Henry Clough of Marconi and has returned in may guises since. Interestingly it was not referred to as the SRPP until quite recently and instead had a variety of other names like 'bootstrap follower' and 'shunt regulated amplifier'. The circuit uses two triodes usually in the same envelope. Each triode is biased identical. The lower triode acts as a common-cathode gain stage with an active load, the upper triode as common-anode gain stage with an identical active load. This is about as close to a complementary transistor pair as valves get. The reason the circuit is push-pull and not single ended is that the signal reaching the bottom triode causes the signal on the grid of the top triode to be in anti phase with it. When the top triode conducts more drive current into the output coupling capacitor, the other conducts less. When the top triode conducts less, charge stored in the capacitor is returned and flows down into the lower triode. Unlike the mu follower, the output should be taken only from the cathode of the upper triode."

The upshot for SRPP is relatively high gain, low output impedance for good drive and even-order harmonic cancellation. The latter is less sweet, creamy and sumptuous than single-ended triode stages to instead emphasize separation and lucidity. And that's exactly what distinguished the Renaissance from my ModWright LS-100. But first a comparison with my Bent Audio Tap-X. As an autoformer passive it makes for a good quasi bypass test. Aside from active gain, what other more or less attributes would the Fonel exhibit versus the not-there neutrality of the AVC?
On "Dragon de Lune" and "Salsa Movar" by the always inspiring Hadouk Trio [Shamanimal] a number of things ticked off. Didier 'bad weed' Malherbe's sax was the more open-throated and reedy with the passive, his transverse flute shinier. Steve Shehan's full-handed bongo trills and accents had more of what the Germans call Schmackes. That's smack squared. Here it was the blistery whipper snap whomp whenever percussive hits not only cracked but followed up with weight. To my mind these aspects were byproducts of speed and the passive went faster. Very much to its credit the Renaissance really wasn't far behind. Without roping in the Tap-X nothing gave away that more uncut rawness was possible. The Fonel meanwhile was heavier in the nether regions to portray more general mass and if less spiky kick then higher overall impact.


There also was very minor glossification of tone textures. Switching to the Bent this patina vanished. The change was most obvious on the saxophone. With the passive it had more bite and nasality, with the valve preamp it was smoother and richer. On Hassan Isakkut's gorgeous "Zindan" from his 2009 release Hayat 1 Hayat his voice in particular but also his sinuous violin had more inner heat and dynamic inflections were the more teased out. Ditto for the exotic timbres in Hector Zazou's "Wanna Mako" from In the House of Mirrors, one of my reference recordings for string tone. My conclusion after various other A/Bs was that of a rather mellow tit for tat. To secure its advantage on speed, incision, lucidity and suchness, the passive had to give up equivalent bits in density, mass and that peculiar inside-out pressurization of tone colors which tubes so often manage in ways that elude transistors.


Surprising was the closeness of either machine. The gap of difference was smaller than usual. This spoke highly to Fonel's noise floor, rise times, low THD and as such their choice of tubes and circuit. To my ears the bottom line of deciding between these two machines came down to a more wall-of-sound feel for the Fonel, a more 'transparent' walk-in i.e. less material impression for the Bent Audio. The usual polarity of cool/warm factored only minutely to confirm that Fonel's designers deliberately situated their Renaissance as closely to transistors as possible without relinquishing the very fine texturizing which still distinguishes their machine as valve based to justify the presence of glowing bits.
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